The general aim of the project is to determine the function of individual CaM kinase II variants in smooth muscle regulation toward the goal of obtaining a complete understanding of the function of this family of protein kinases in smooth muscle. I have already identified six variants of CaM kinase II gamma, as cDNAs, from a ferret aorta cDNA library. Their in vitro functions differ in terms of autophosphorylation and substrate phosphorylation. This suggests that they will also function differentially in the cell. The proposed study will be undertaken with the specific aims i) To test the hypothesis that all six variants of CaM kinase II gamma identified as cDNAs from an aorta cDNA library are expressed as protein in smooth muscle tissue; 2) To test the hypothesis that different variants of CaM kinase II gamma have differential functions; 3) To test the hypothesis that multiple variants of CaM kinase II delta are also expressed and contribute to the regulation of smooth muscle. Technologies to be used include, cloning, quantitative RT-PCR, mass spec sequencing, antisense knockdown, confocal microscopy and protein kinase assays.